PH Testing Sensor Module ph(0-14) acidity sensitive

Overview:
PH(0-14) Value Detect Sensor Module
Features:
Heating voltage: 5 ± 0.2V (AC DC)
Working current: 5-10mA
Detectable concentration range: PH0-14
Detection Temperature range: 0-80 ℃
Response time:≤5S
Settling Time:≤60S
Component Power:≤0.5W
Working temperature:-10-50 ℃ (nominal temperature 20 ℃)
Humidity: 95% RH (nominal humidity 65% RH)
Module Size: 42mm × 32mm × 20mm
Output:analog voltage signal output
With 4pcs M3 Mounting Holes

Note:
The color of item might be slightly different from the picture shown, which mainly lies in different light effect and computer monitor. Please give us your understanding. Thank you!
PH Electrode Probe BNC For Arduino:
The PH electrode has a single cylinder that allows direct connection to the input terminal of a PH meter, controller, or any PH device which has a BNC input terminal.
The PH electrode probe is accurate and reliable that can gives almost instantaneous readings.

Features:
PH range: 0-14 PH
Temperature range: 0-80℃
Zero-point: 7 ± 0.25PH
Alkali Error: ≤15 mv
Theoretical Percentage Slope: ≧98%
Internal Resistance: ≦250MΩ
Response Time: ≦1min
Operating Temperature: 0-60℃
Terminal Blocks: BNC plug
BNC Connector suitable for most PH meter and controller.
Suitable for wide range of application: Aquariums, Hydroponics, Laboratory etc.
Package Includes:
1pcs ph Sensor Module

Pinout:

TO – Temperature output

DO – 3.3V pH limit trigger

PO – PH analog output

Gnd – Gnd for PH probe

Gnd – Gnd for board

VCC – 5V DC

POT 1 – Analog reading offset (Nearest to BNC connector)

POT 2 – PH limit setting

Calibration:

This board have the ability to supply a voltage output to the analogue board that will represent a PH value just like any other sensor that will connect to an analog pin.

Looks like PH=0 should be presented by 0V output and a PH=14 to represent 5V, but… NO

Neutral PH=7 set to 0V, this means that the voltage will go into the minuses when reading acidic PH values and obviously cannot be read by the analog Arduino port.

The offset pot is used to change this so that a PH=7 will read the expected 2.5V to the Arduino analog pin, the analog pin can read voltages between 0V and 5V hence the 2.5V that is halfway between 0V and 5V as a PH=7 is halfway between PH 0 and PH 14.

You will need to turn the offset potentiometer to get the right offset, the offset pot is the blue pot nearest to the BNC connector.

To set the offset is fairly easy.

1. Disconnect the probe short-circuit the BNC connector.
2. Use your multimeter to adjust the offset potentiometer until PO measures 2.5V
3. Done

Wiring diagram:

1. PO => Arduino A0
2. GND =>Arduino GND
3. GND =>Arduino GND

Source code:

#include <Arduino.h>

int pHSense = A0;
int samples = 10;
float adc_resolution = 1024.0;

void setup()
{
    Serial.begin(9600);
    delay(100);
    Serial.println("cimpleo pH Sense");
}

float ph (float voltage) {
    return 7 + ((2.5 - voltage) / 0.18);
}

void loop()
{
    int measurings=0;

    for (int i = 0; i < samples; i++)
    {
        measurings += analogRead(pHSense);
        delay(10);

    }

    float voltage = 5 / adc_resolution * measurings/samples;
    Serial.print("pH= ");
    Serial.println(ph(voltage));
    delay(3000);
}